not 100% sure what you talking about there. but it means that if you check in at 45 minutes before your flight, sw will pay to have your bag delivered if it misses the flight. 44 minutes or less, they will take it 'late checked' and wont guarantee it to make the flight due to long tsa screening processes. and tsa do take their time. you can check your bag in a few minutes to departure time, but it prolly wont make the flight, and you prolly wont either.